The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventor, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Generally, the size of cellular phones and other mobile devices has been reduced to improve mobility and storage while functionality has increased. For example, cellular phones may include cameras, MP3 players, personal digital assistants (PDAs), WiFi and/or other network interfaces, Bluetooth interfaces, and/or other devices. The increased functionality tends to increase the complexity of controls and user inputs of the cellular phones. Since these devices rely on battery power, low power consumption is also an important consideration.
Typically, one or more buttons for controlling the functions of the cellular phone are located on an external surface of the cellular phone. For example, buttons for initiating calls or operating an accessory such as a camera may be located on the external surface. Even clamshell-type cellular phones may have external buttons that may activate an external display or other functions of the cellular phone, even when the cellular phone is closed. The external buttons may be susceptible to inadvertent button presses. For example, users often store or transport the cellular phone in a pocket or purse. Inadvertent contact with one of the external buttons during storage may initiate a call or other function of the cellular phone, or otherwise unnecessarily consume power. Further, incidental pressure or movement during storage may also inadvertently actuate one or more unexposed buttons on a keypad of the cellular phone. For example, pressure on a top portion of a flip-type or clamshell-type phone may cause the top portion to actuate buttons on a bottom portion of the phone. These inadvertent button presses tend to increase power consumption, which reduces battery life.